The Contractor shall perform immunotoxicity studies, including hypersensitivity and immunosuppression, on various environmental chemicals and therapeutic drugs. Initially, the Contractor will be required to demonstrate proficiency in the uses of the immune testing panels using one known chemical. If approved by the Project Officer, the Contractor shall proceed to Tasks II & III. Task II shall consist of Dose Range Finding studies, Immune Function Testing, Host Resistance Assays, and Mouse Skin Hypersensitivity studies. Task III shall involve development and implementation of new methodology.